1986 Mazda RX-7 FC s4
13B NA
Stock ignition and ECU
My car is a crank but won’t start
The tachometer bounces
There is good fuel
Here’s what I’ve already tested. I’ve done a bunch of troubleshooting that I’m starting to second guess myself but I think this is everything
Battery is brand new.
Spark plug wires ~1 year old
Spark plugs brand new
Checked CAS resistance = good.
Checked coil pack resistance = good.
Harness side Black/Yellow wire has steady 12V with key ON.
Coil pack itself still reads 0V when plugged in.
Tried a second coil pack/igniter — same result.
Cleaned coil/igniter ground.
Still no spark output.
Does this sound more like an igniter failure or ECU failure on an FC? Anything else I should test before swapping parts?
by No_Section_4947
3 Comments
This is going to sound dumb, are the battery and spark plugs like, fresh install new and now doesn’t work? Or you’ve been using them before fine?
Because I’d start there if they’re fresh
You missed telling us how this came to be. Was it a broken down car in a garage that you can keep if you get it running or was it running yesterday perfectly and now it’s busted?
Low compression, probably. Engine rebuild.